osmo-bts-virtual: Port over to osmo_io

osmo_io permits us to use the io_uring backend, which should
significantly speed up the many small read/writes we're doing
on virt-um.

Change-Id: Icfe42da00fd446c38090055e2baa5d5e0ae5b70c

4 files changed, 100 insertions, 91 deletions

diff --git a/src/osmo-bts-virtual/osmo_mcast_sock.c b/src/osmo-bts-virtual/osmo_mcast_sock.c
index 3e565142..c802e02d 100644
--- a/src/osmo-bts-virtual/osmo_mcast_sock.c
+++ b/src/osmo-bts-virtual/osmo_mcast_sock.c
@@ -3,6 +3,7 @@
 #include <netdb.h>
 #include <osmocom/core/socket.h>
 #include <osmocom/core/select.h>
+#include <osmocom/core/osmo_io.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
@@ -10,102 +11,133 @@
 #include <unistd.h>
 #include "osmo_mcast_sock.h"
 
+static void noop_write_cb(struct osmo_io_fd *iofd, int res, struct msgb *msg)
+{
+	/* nothing */
+}
+
+static const struct osmo_io_ops srv_ioops = {
+	/* no read call-back as we don't read from the socket */
+	/* libosmcoore before change-id I0c071a29e508884bac331ada5e510bbfcf440bbf requires write call-back
+	 * even if we don't care about it */
+	.write_cb = noop_write_cb,
+};
+
 /* server socket is what we use for transmission. It is not subscribed
  * to a multicast group or locally bound, but it is just a normal UDP
  * socket that's connected to the remote mcast group + port */
-int mcast_server_sock_setup(struct osmo_fd *ofd, const char* tx_mcast_group,
-			    uint16_t tx_mcast_port, bool loopback)
+static struct osmo_io_fd *
+mcast_server_sock_setup(void *ctx, const char *tx_mcast_group, uint16_t tx_mcast_port, bool loopback)
 {
-	int rc;
+	int rc, fd;
 	unsigned int flags = OSMO_SOCK_F_CONNECT | OSMO_SOCK_F_UDP_REUSEADDR;
+	struct osmo_io_fd *iofd;
 
 	if (!loopback)
 		flags |= OSMO_SOCK_F_NO_MCAST_LOOP;
 
 	/* setup mcast server socket */
-	rc = osmo_sock_init_ofd(ofd, AF_INET, SOCK_DGRAM, IPPROTO_UDP,
-				tx_mcast_group, tx_mcast_port, flags);
+	rc = osmo_sock_init(AF_INET, SOCK_DGRAM, IPPROTO_UDP, tx_mcast_group, tx_mcast_port, flags);
 	if (rc < 0) {
 		perror("Failed to create Multicast Server Socket");
-		return rc;
+		return NULL;
 	}
+	fd = rc;
 
-	return 0;
+	iofd = osmo_iofd_setup(ctx, rc, "mcast_server_sock", OSMO_IO_FD_MODE_READ_WRITE, &srv_ioops, NULL);
+	if (!iofd) {
+		close(fd);
+		return NULL;
+	}
+
+	osmo_iofd_register(iofd, -1);
+	return iofd;
+}
+
+static void mcast_sock_read_cb(struct osmo_io_fd *iofd, int res, struct msgb *msg)
+{
+	struct mcast_bidir_sock *bidir_sock = osmo_iofd_get_data(iofd);
+	bidir_sock->read_cb(res, msg, bidir_sock->data);
 }
 
+const struct osmo_io_ops clnt_ioops = {
+	.read_cb = mcast_sock_read_cb,
+	/* no write call-back as we don't write to the socket */
+};
+
 /* the client socket is what we use for reception.  It is a UDP socket
  * that's bound to the GSMTAP UDP port and subscribed to the respective
  * multicast group */
-int mcast_client_sock_setup(struct osmo_fd *ofd, const char *mcast_group, uint16_t mcast_port,
-			    int (*fd_rx_cb)(struct osmo_fd *ofd, unsigned int what),
-			    void *osmo_fd_data)
+static struct osmo_io_fd *
+mcast_client_sock_setup(void *ctx, const char *mcast_group, uint16_t mcast_port,
+			void (*read_cb)(int rc, struct msgb *msg, void *data))
 {
-	int rc;
+	int rc, fd;
 	unsigned int flags = OSMO_SOCK_F_BIND | OSMO_SOCK_F_NO_MCAST_ALL | OSMO_SOCK_F_UDP_REUSEADDR;
-
-	osmo_fd_setup(ofd, -1, OSMO_FD_READ, fd_rx_cb, osmo_fd_data, 0);
+	struct osmo_io_fd *iofd;
 
 	/* Create mcast client socket */
-	rc = osmo_sock_init_ofd(ofd, AF_INET, SOCK_DGRAM, IPPROTO_UDP,
-				NULL, mcast_port, flags);
+	rc = osmo_sock_init(AF_INET, SOCK_DGRAM, IPPROTO_UDP, NULL, mcast_port, flags);
 	if (rc < 0) {
 		perror("Could not create mcast client socket");
-		return rc;
+		return NULL;
 	}
+	fd = rc;
 
 	/* Configure and join the multicast group */
-	rc = osmo_sock_mcast_subscribe(ofd->fd, mcast_group);
+	rc = osmo_sock_mcast_subscribe(fd, mcast_group);
 	if (rc < 0) {
 		perror("Failed to join to mcast goup");
-		osmo_fd_close(ofd);
-		return rc;
+		close(fd);
+		return NULL;
+	}
+
+	iofd = osmo_iofd_setup(ctx, fd, "mcast_client_sock", OSMO_IO_FD_MODE_READ_WRITE, &clnt_ioops, ctx);
+	if (!iofd) {
+		close(fd);
+		return NULL;
 	}
 
-	return 0;
+	osmo_iofd_register(iofd, -1);
+	return iofd;
 }
 
 struct mcast_bidir_sock *
 mcast_bidir_sock_setup(void *ctx, const char *tx_mcast_group, uint16_t tx_mcast_port,
 			const char *rx_mcast_group, uint16_t rx_mcast_port, bool loopback,
-			int (*fd_rx_cb)(struct osmo_fd *ofd, unsigned int what),
-			void *osmo_fd_data)
+			void (*read_cb)(int rc, struct msgb *msg, void *data),
+			void *data)
 {
 	struct mcast_bidir_sock *bidir_sock = talloc(ctx, struct mcast_bidir_sock);
-	int rc;
 
 	if (!bidir_sock)
 		return NULL;
 
-	rc = mcast_client_sock_setup(&bidir_sock->rx_ofd, rx_mcast_group, rx_mcast_port,
-				fd_rx_cb, osmo_fd_data);
-	if (rc < 0) {
+	bidir_sock->read_cb = read_cb;
+	bidir_sock->data = data;
+
+	bidir_sock->rx_iofd = mcast_client_sock_setup(bidir_sock, rx_mcast_group, rx_mcast_port, read_cb);
+	if (!bidir_sock->rx_iofd) {
 		talloc_free(bidir_sock);
 		return NULL;
 	}
-	rc = mcast_server_sock_setup(&bidir_sock->tx_ofd, tx_mcast_group, tx_mcast_port, loopback);
-	if (rc < 0) {
-		osmo_fd_close(&bidir_sock->rx_ofd);
+	bidir_sock->tx_iofd = mcast_server_sock_setup(bidir_sock, tx_mcast_group, tx_mcast_port, loopback);
+	if (!bidir_sock->tx_iofd) {
+		osmo_iofd_free(bidir_sock->rx_iofd);
 		talloc_free(bidir_sock);
 		return NULL;
 	}
 	return bidir_sock;
-
-}
-
-int mcast_bidir_sock_tx(struct mcast_bidir_sock *bidir_sock, const uint8_t *data,
-                        unsigned int data_len)
-{
-	return send(bidir_sock->tx_ofd.fd, data, data_len, 0);
 }
 
-int mcast_bidir_sock_rx(struct mcast_bidir_sock *bidir_sock, uint8_t *buf, unsigned int buf_len)
+int mcast_bidir_sock_tx_msg(struct mcast_bidir_sock *bidir_sock, struct msgb *msg)
 {
-	return recv(bidir_sock->rx_ofd.fd, buf, buf_len, 0);
+	return osmo_iofd_write_msgb(bidir_sock->tx_iofd, msg);
 }
 
 void mcast_bidir_sock_close(struct mcast_bidir_sock *bidir_sock)
 {
-	osmo_fd_close(&bidir_sock->tx_ofd);
-	osmo_fd_close(&bidir_sock->rx_ofd);
+	osmo_iofd_free(bidir_sock->tx_iofd);
+	osmo_iofd_free(bidir_sock->rx_iofd);
 	talloc_free(bidir_sock);
 }
diff --git a/src/osmo-bts-virtual/osmo_mcast_sock.h b/src/osmo-bts-virtual/osmo_mcast_sock.h
index aa2013c6..5f68415b 100644
--- a/src/osmo-bts-virtual/osmo_mcast_sock.h
+++ b/src/osmo-bts-virtual/osmo_mcast_sock.h
@@ -4,26 +4,20 @@
 #include <stdint.h>
 #include <netinet/in.h>
 #include <osmocom/core/select.h>
+#include <osmocom/core/osmo_io.h>
 
 struct mcast_bidir_sock {
-	struct osmo_fd tx_ofd;
-	struct osmo_fd rx_ofd;
+	struct osmo_io_fd *tx_iofd;
+	struct osmo_io_fd *rx_iofd;
+	void (*read_cb)(int rc, struct msgb *msg, void *data);
+	void *data;
 };
 
-struct mcast_bidir_sock *mcast_bidir_sock_setup(void *ctx,
-                const char *tx_mcast_group, uint16_t tx_mcast_port,
-                const char *rx_mcast_group, uint16_t rx_mcast_port, bool loopback,
-                int (*fd_rx_cb)(struct osmo_fd *ofd, unsigned int what),
-                void *osmo_fd_data);
+struct mcast_bidir_sock *
+mcast_bidir_sock_setup(void *ctx, const char *tx_mcast_group, uint16_t tx_mcast_port,
+			const char *rx_mcast_group, uint16_t rx_mcast_port, bool loopback,
+			void (*read_cb)(int rc, struct msgb *msg, void *data),
+			void *data);
 
-int mcast_server_sock_setup(struct osmo_fd *ofd, const char *tx_mcast_group,
-			    uint16_t tx_mcast_port, bool loopback);
-
-int mcast_client_sock_setup(struct osmo_fd *ofd, const char *mcast_group, uint16_t mcast_port,
-			    int (*fd_rx_cb)(struct osmo_fd *ofd, unsigned int what),
-			    void *osmo_fd_data);
-
-int mcast_bidir_sock_tx(struct mcast_bidir_sock *bidir_sock, const uint8_t *data, unsigned int data_len);
-int mcast_bidir_sock_rx(struct mcast_bidir_sock *bidir_sock, uint8_t *buf, unsigned int buf_len);
+int mcast_bidir_sock_tx_msg(struct mcast_bidir_sock *bidir_sock, struct msgb *msg);
 void mcast_bidir_sock_close(struct mcast_bidir_sock* bidir_sock);
-
diff --git a/src/osmo-bts-virtual/scheduler_virtbts.c b/src/osmo-bts-virtual/scheduler_virtbts.c
index 1bcec063..87596a79 100644
--- a/src/osmo-bts-virtual/scheduler_virtbts.c
+++ b/src/osmo-bts-virtual/scheduler_virtbts.c
@@ -102,8 +102,6 @@ static void _tx_to_virt_um(struct l1sched_ts *l1ts,
 		if (rc < 0)
 			LOGL1SB(DL1P, LOGL_ERROR, l1ts, br,
 			       "GSMTAP msg could not send to virtual Um: %s\n", strerror(-rc));
-		else if (rc == 0)
-			bts_shutdown(trx->bts, "VirtPHY write socket died\n");
 		else
 			LOGL1SB(DL1P, LOGL_DEBUG, l1ts, br,
 			       "Sending GSMTAP message to virtual Um\n");
diff --git a/src/osmo-bts-virtual/virtual_um.c b/src/osmo-bts-virtual/virtual_um.c
index 44747fa6..711e75d3 100644
--- a/src/osmo-bts-virtual/virtual_um.c
+++ b/src/osmo-bts-virtual/virtual_um.c
@@ -32,33 +32,15 @@
 #include <errno.h>
 
 /**
- * Virtual UM interface file descriptor callback.
- * Should be called by select.c when the fd is ready for reading.
+ * Virtual UM interface file descriptor read callback.
  */
-static int virt_um_fd_cb(struct osmo_fd *ofd, unsigned int what)
+static void virt_um_read_cb(int rc, struct msgb *msg, void *data)
 {
-	struct virt_um_inst *vui = ofd->data;
+	struct virt_um_inst *vui = data;
+	msg->l1h = msg->data;
 
-	if (what & OSMO_FD_READ) {
-		struct msgb *msg = msgb_alloc(VIRT_UM_MSGB_SIZE, "Virtual UM Rx");
-		int rc;
-
-		/* read message from fd into message buffer */
-		rc = mcast_bidir_sock_rx(vui->mcast_sock, msgb_data(msg), msgb_tailroom(msg));
-		if (rc > 0) {
-			msgb_put(msg, rc);
-			msg->l1h = msgb_data(msg);
-			/* call the l1 callback function for a received msg */
-			vui->recv_cb(vui, msg);
-		} else if (rc == 0) {
-			vui->recv_cb(vui, NULL);
-			osmo_fd_close(ofd);
-		} else
-			perror("Read from multicast socket");
-
-	}
-
-	return 0;
+	/* call the l1 callback function for a received msg */
+	vui->recv_cb(vui, msg);
 }
 
 struct virt_um_inst *virt_um_init(void *ctx, char *tx_mcast_group, uint16_t tx_mcast_port,
@@ -69,7 +51,7 @@ struct virt_um_inst *virt_um_init(void *ctx, char *tx_mcast_group, uint16_t tx_m
 	int rc;
 
 	vui->mcast_sock = mcast_bidir_sock_setup(ctx, tx_mcast_group, tx_mcast_port,
-						 rx_mcast_group, rx_mcast_port, 1, virt_um_fd_cb, vui);
+						 rx_mcast_group, rx_mcast_port, 1, virt_um_read_cb, vui);
 	if (!vui->mcast_sock) {
 		perror("Unable to create VirtualUm multicast socket");
 		talloc_free(vui);
@@ -79,7 +61,8 @@ struct virt_um_inst *virt_um_init(void *ctx, char *tx_mcast_group, uint16_t tx_m
 
 	/* -1 means default, i.e. no TTL explicitly configured in VTY */
 	if (ttl >= 0) {
-		rc = osmo_sock_mcast_ttl_set(vui->mcast_sock->tx_ofd.fd, ttl);
+		int txfd = osmo_iofd_get_fd(vui->mcast_sock->tx_iofd);
+		rc = osmo_sock_mcast_ttl_set(txfd, ttl);
 		if (rc < 0) {
 			perror("Cannot set TTL of Virtual Um transmit socket");
 			goto out_close;
@@ -87,12 +70,14 @@ struct virt_um_inst *virt_um_init(void *ctx, char *tx_mcast_group, uint16_t tx_m
 	}
 
 	if (dev_name) {
-		rc = osmo_sock_mcast_iface_set(vui->mcast_sock->tx_ofd.fd, dev_name);
+		int txfd = osmo_iofd_get_fd(vui->mcast_sock->tx_iofd);
+		rc = osmo_sock_mcast_iface_set(txfd, dev_name);
 		if (rc < 0) {
 			perror("Cannot bind multicast tx to given device");
 			goto out_close;
 		}
-		rc = osmo_sock_mcast_iface_set(vui->mcast_sock->rx_ofd.fd, dev_name);
+		int rxfd = osmo_iofd_get_fd(vui->mcast_sock->rx_iofd);
+		rc = osmo_sock_mcast_iface_set(rxfd, dev_name);
 		if (rc < 0) {
 			perror("Cannot bind multicast rx to given device");
 			goto out_close;
@@ -120,11 +105,11 @@ int virt_um_write_msg(struct virt_um_inst *vui, struct msgb *msg)
 {
 	int rc;
 
-	rc = mcast_bidir_sock_tx(vui->mcast_sock, msgb_data(msg),
-	                msgb_length(msg));
-	if (rc < 0)
+	rc = mcast_bidir_sock_tx_msg(vui->mcast_sock, msg);
+	if (rc < 0) {
+		msgb_free(msg);
 		rc = -errno;
-	msgb_free(msg);
+	}
 
 	return rc;
 }